Lupus erythematosus profundus (lupus panniculitis) induced by interferon-beta in a multiple sclerosis patient.

We report a patient with multiple sclerosis (MS) who developed subcutaneous nodules on the face, shoulders and extremities while being treated with interferon (IFN)-beta-1b. These nodules fluctuated in parallel with myelopathy, and were diagnosed as lupus erythematosus profundus (LEP) based on histopathological findings. The patient showed no relapse of either neurological symptoms or subcutaneous nodules after cessation of IFN-beta-1b. This agent can cause induration and necrosis in the sites of injection but also systemic skin lesions such as LEP ascribable to its immunomodulatory effects.